In recent years, the production of lithium-ion batteries has grown rapidly, the application field has been expanding, according to market research, by 2010, the demand for lithium-ion batteries can reach about 1.35 billion, has become a high-tech product of great significance to the national economy and people's lives in the 21st century. 1. Chemicalbook3 propane sultone (PS) as the preparation of lithium ion secondary electrolyte basic functional additives, its purity directly affects the quality of the electrolyte, the current domestic market sold PS, purity is about 99.5%, can not meet the battery grade requirements (purity > 99.9%).